951 Oil Consumption
Discussion
This question has been asked before by someone else, but I've searched and searched and can't find the posts in question.
My 951 is going through a bit of oil, chucks out bit of smoke, especially when the boost comes on strong and generaly leaves oily soot on anyone who parks too close to the exhaust.
Rings, vlaves, turbo and I think I recall someone saying the turbo can suck oil out of the engine under certain conditions resulting in high consumption. Anyone know how this works or from the symptoms is it more likely to be one or more of the others.
It's an 87 220 HP with 124k on the clock, has all the right stamps but not too much history in terms of work done since 97. Pulls well, with no tail off in accelleration that canbe noticed at anything resembling legal speeds.
Any thoughts or advice are most appreciated.
>> Edited by ripton on Saturday 14th January 22:54
My 951 is going through a bit of oil, chucks out bit of smoke, especially when the boost comes on strong and generaly leaves oily soot on anyone who parks too close to the exhaust.
Rings, vlaves, turbo and I think I recall someone saying the turbo can suck oil out of the engine under certain conditions resulting in high consumption. Anyone know how this works or from the symptoms is it more likely to be one or more of the others.
It's an 87 220 HP with 124k on the clock, has all the right stamps but not too much history in terms of work done since 97. Pulls well, with no tail off in accelleration that canbe noticed at anything resembling legal speeds.
Any thoughts or advice are most appreciated.
>> Edited by ripton on Saturday 14th January 22:54
It could be many things but first get the Turbo itself checked (easily done by removing the rubber boot leading to it) as the oil seals degrade over time. Your intercooler will probably be dripping with oil residue if this is the case
Also get a compression test and a cylinder leakdown test to determine if its either the piston rings or the valve sealing thats causing the oil leakage.
How much oil do you use? Mine used to use a litre for every 2k of road miles or every 200 track miles :O
Also get a compression test and a cylinder leakdown test to determine if its either the piston rings or the valve sealing thats causing the oil leakage.
How much oil do you use? Mine used to use a litre for every 2k of road miles or every 200 track miles :O
Run a compression and leakdown check, if you do not have the tools to do this, get a garage (ideally a specialist) to do it for you.
Remove the intake boot between the airflow meter and the turbo.. is it covered in oil? If so you probably have a breather issue.
Remove the hard intake boot between the turbo and the left hand side of the intercooler... is it coated in oil? If it is, yet the intake boot between the turbo and airflow meter is dry, you have compressor turbo oil seal issues.. If both are oily, are they equally oily? if so, you have a breather issue.
If both of these are dry, you can rule out breather and turbo compressor side oil seal issues.
Next, are you plug electrodes oily? if so, and the intake boots are dry, you have ring or valve guide issues..
While the intake boot between the turbo and airflow meter is off... try to wiggle the end of the turbo shaft.. any play in it? if so, have it checked out by a specialist with the correct measuring equipment
I would probably bet on it being as simple as a breather issue.. especially if the car is modified.
We tend to find that 944 turbo's we have modified, as the power passes about 330 BHP the breather system is unable to cope on a fit engine.. if the breather system is faulty or aged, it can even cause problems on standard cars. After 330 BHP we always use a modified breather system
Remove the intake boot between the airflow meter and the turbo.. is it covered in oil? If so you probably have a breather issue.
Remove the hard intake boot between the turbo and the left hand side of the intercooler... is it coated in oil? If it is, yet the intake boot between the turbo and airflow meter is dry, you have compressor turbo oil seal issues.. If both are oily, are they equally oily? if so, you have a breather issue.
If both of these are dry, you can rule out breather and turbo compressor side oil seal issues.
Next, are you plug electrodes oily? if so, and the intake boots are dry, you have ring or valve guide issues..
While the intake boot between the turbo and airflow meter is off... try to wiggle the end of the turbo shaft.. any play in it? if so, have it checked out by a specialist with the correct measuring equipment
I would probably bet on it being as simple as a breather issue.. especially if the car is modified.
We tend to find that 944 turbo's we have modified, as the power passes about 330 BHP the breather system is unable to cope on a fit engine.. if the breather system is faulty or aged, it can even cause problems on standard cars. After 330 BHP we always use a modified breather system
Thanks Jon, comprehensive checklist!
Have just googled "leakdown test" and I dont have the kit. But I may know a man who has.
Will run through the rest of them at the weekend.
How easliy fixed is the breather if that is what has gone u/s? I've got a fairly good idea of the work required on the others and, apart from fixing sick turbos, am confident that I've either got the knowledge and kit to do the job or know someone who can help out.
Cheers
Chris
Have just googled "leakdown test" and I dont have the kit. But I may know a man who has.
Will run through the rest of them at the weekend.
How easliy fixed is the breather if that is what has gone u/s? I've got a fairly good idea of the work required on the others and, apart from fixing sick turbos, am confident that I've either got the knowledge and kit to do the job or know someone who can help out.
Cheers
Chris
Hi guys,
the motor itself could be in PERFECT condition and the oil prressurized bearing on the turbocharger could be going out, putting oil into the exhaust system. This happened to me on a turbo Volvo a while back.
If the car used the wrong (non-turbo specified) oil, or if the PO revved up the motor and then had a habit of shutting off the motor (while the turbo continued to spin at 100,000 rpm with no oil) the bearing could well be the issue here.
Dogsharks
the motor itself could be in PERFECT condition and the oil prressurized bearing on the turbocharger could be going out, putting oil into the exhaust system. This happened to me on a turbo Volvo a while back.
If the car used the wrong (non-turbo specified) oil, or if the PO revved up the motor and then had a habit of shutting off the motor (while the turbo continued to spin at 100,000 rpm with no oil) the bearing could well be the issue here.
Dogsharks
ripton said:
Cheers for that.
Whats the best oil for the job, you get told so many things by so many different people.
Chris
That's because there's more than one correct answer. There are alot of oils that will do an equal job in your car, many oils are over engineered for road car applications
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